【WPF】一个简单的ColorPicker控件

在斯克迪亚看到一篇WPF动态改变主题颜色的文章，来了兴趣，于是自己搞了个简单的ColorPicker控件。

 

控件其实很简单，定义了5个依赖属性 

FinalBrushProperty, AProperty, RProperty, GProperty, BProperty

然后当A,R,G,B发生变化时，构造新的FinalBrush

在FinalBrush发生变化时，更新ARGB的值。

 private static void OnFinalBrushChanged(DependencyObject sender, DependencyPropertyChangedEventArgs e)
        {
            ColorPicker picker = sender as ColorPicker;
            Color newColor = ((SolidColorBrush)e.NewValue).Color;
            picker.A = newColor.A;
            picker.R = newColor.R;
            picker.G = newColor.G;
            picker.B = newColor.B;
            picker.RaiseEvent(new FinalBrushChangedEventArgs(FinalBrushChangedEvent, picker, (SolidColorBrush)e.OldValue, (SolidColorBrush)e.NewValue));
        }

 private static void OnColorChanged(DependencyObject sender, DependencyPropertyChangedEventArgs e)
        {
            ColorPicker picker = sender as ColorPicker;
            picker.FinalBrush = new SolidColorBrush(Color.FromArgb(picker.A, picker.R, picker.G, picker.B));
        }

在ColorPicker的模板里面，分别放置4个Slider绑定到ARGB，一个Border绑定到FinalBrush以预览结果。

<Style TargetType="{x:Type local:ColorPicker}">          
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="{x:Type local:ColorPicker}">
                    <Border Background="{TemplateBinding Background}"
                            BorderBrush="{TemplateBinding BorderBrush}"
                            BorderThickness="{TemplateBinding BorderThickness}">
                        <DockPanel>
                            <Border CornerRadius="5" BorderBrush="Black" BorderThickness="1" 
                                    Width="60" Height="60" Margin="10"
                                    Background="{TemplateBinding FinalBrush}"/>
                            <Grid>
                                <Grid.Resources>
                                    <Style TargetType="{x:Type Slider}">
                                        <Setter Property="VerticalAlignment" Value="Center"/>
                                        <Setter Property="Minimum" Value="0"/>
                                        <Setter Property="Maximum" Value="255"/>
                                        <Setter Property="SmallChange" Value="1"/>
                                        <Setter Property="LargeChange" Value="15"/>
                                        <Setter Property="Grid.Column" Value="1"/>
                                    </Style>
                                    <Style TargetType="{x:Type TextBlock}">
                                        <Setter Property="VerticalAlignment" Value="Center"/>
                                        <Setter Property="HorizontalAlignment" Value="Right"/>
                                        <Setter Property="Grid.Column" Value="0"/>
                                    </Style>
                                </Grid.Resources>
                                <Grid.ColumnDefinitions>
                                    <ColumnDefinition Width="65"/>
                                    <ColumnDefinition/>
                                </Grid.ColumnDefinitions>
                                <Grid.RowDefinitions>
                                    <RowDefinition/>
                                    <RowDefinition/>
                                    <RowDefinition/>
                                    <RowDefinition/>
                                </Grid.RowDefinitions>
                                <TextBlock Grid.Row="0" Text="Alpha"/>
                                <TextBlock Grid.Row="1" Text="Red"/>
                                <TextBlock Grid.Row="2" Text="Green"/>
                                <TextBlock Grid.Row="3"  Text="Blue"/>
                                <Slider Grid.Row="0" Value="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=A, Mode=TwoWay}"/>
                                <Slider Grid.Row="1" Value="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=R, Mode=TwoWay}"/>
                                <Slider Grid.Row="2" Value="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=G, Mode=TwoWay}"/>
                                <Slider Grid.Row="3" Value="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=B, Mode=TwoWay}"/>
                            </Grid>
                        </DockPanel>
                    </Border>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>

这个时候，ColorPicker就可以使用了。在Demo里面，我做了一个ColorPickerDialog。它继承自Window，里面放了一个ColorPicker控件，然后将它的FinalBrush属性绑定到资源中的WindowBackground上。这样打开Dialog的时候，它的颜色自动和资源的颜色同步。同时，监听它的ColorPicker的FinalBrushChanged事件，更新资源中的颜色。这样，当我们调节ColorPickerDialog的颜色的时候，Window的颜色同步变化。

当然，你可以做的更完善，比如添加一个确定和取消按钮，当取消的时候恢复原来的颜色。或者放一个CheckBox，指定是否同步预览。

我的美工功底比斯克迪亚差远了，呵呵，就是原始的样式。

源代码下载：https://files.cnblogs.com/RMay/ChangeColor.rar

晕啊，用Chrome编辑有问题。